feat: implement Longest() for stdlib compatibility (Fixes #26) - #27
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…#26) - Add longest bool flag to Regex struct - Implement SetLongest() in meta.Engine and PikeVM - Modify searchUnanchoredAt and searchUnanchoredWithCapturesAt for longest support - Modify searchAt and searchAtWithCaptures for longest support - Fix misleading documentation (was claiming leftmost-longest by default) - Add TestLongest and TestLongestMatchesStdlib tests - No performance regression in default (leftmost-first) mode Default: leftmost-first (Perl semantics) - first alternative wins Longest(): leftmost-longest (POSIX semantics) - longest match wins Example: re := coregex.MustCompile(`(a|ab)`) re.FindString("ab") // "a" (default: first branch wins) re.Longest() re.FindString("ab") // "ab" (longest match wins)
Benchmark ComparisonComparing Summary:
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The linter was complaining about gocognit (>40) and nestif (>6) in the longest match logic. Extracted match comparison into isBetterMatch() helper method and simplified the remaining match detection blocks.
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Summary
Implements proper
Longest()method that switches from leftmost-first (Perl) to leftmost-longest (POSIX) matching semantics.Before:
Longest()was a no-op stub with misleading documentation claiming coregex used leftmost-longest by default.After:
Longest()actually works, matching Go stdlibregexp.Regexp.Longest()behavior.Changes
longest boolflag toRegexstructSetLongest()inmeta.Engineandnfa.PikeVMsearchUnanchoredAt()searchUnanchoredWithCapturesAt()searchAt()searchAtWithCaptures()Behavior
(a|ab)(#|#!)(cat|catalog)Performance
No regression in default mode!
Test plan
go test ./...passesTestLongest- verifies behavior change after Longest()TestLongestMatchesStdlib- verifies match with Go stdlibFixes #26